1. Frequency Distributions and Histograms
Lesson 1.8
Frequency Distributions and Histograms

2. Frequency Table
Shows how often an item appears in a set of data. A tally mark is used to record each response.

3. Use the frequency table of Brad’s data.
Program
Tally
Frequency
Sports
IIII II 7
Mysteries
IIII 4
Soap Operas 5
News
Quiz Shows
IIII I 6
Music Videos II 2
Adventures
IIII IIII 9
Comedies
IIII II
How many people chose sports programs over news?
Which two programs together have the same frequency as adventures?

4. Histogram Differences between a Bar Graph and a Histogram:
A special type of bar graph.
Differences between a Bar Graph and a Histogram:
1. A bar graph displays separate categories while a histogram displays data grouped into intervals.
2. Bars in a bar graph have spaces, while the bars in a histogram do not.

5. How to determine intervals:
The first interval is given.
Determine how big that interval is and make each following interval the same until all of the data has been analyzed.

6. Practice
Make a Frequency Distribution using the given data.
29, 30, 38, 39, 43, 42, 50, 49, 48, 47, 35, 29, 35, 34, 36, 38, 41, 41
1st Interval: 29-32

7. Practice Make a Histogram using the given data.
67, 68, 72, 73, 77, 81, 83, 83, 86, 88, 91, 95, 95, 98, 98, 100
Make the first interval 66-70

8. Homework
Page , 25-38